Container with functions of temperature indication and thermal storage

ABSTRACT

A container with functions of temperature indication and thermal storage is provided. The container includes: an inner bottle containing a liquid, a thermochromic and thermal storage material layer disposed on the outer side of the inner bottle, and a first polymer layer disposed on the outer side of the thermochromic and thermal storage material layer. The thermochromic and thermal storage material layer comprises a thermal storage material and a thermochromic material. The thermal storage material is adapted to undergo a phase change for absorption or release of thermal energy. The thermochromic material is mixed in the thermal storage material and having at least two color changes depending on a temperature change. Wherein, the first polymer layer includes a wavelength-selective polymer, and the thermochromic and thermal storage material layer absorbs light passing through the first polymer layer.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Taiwan Patent Application No. 107114252, filed on Apr. 26, 2018, in the Taiwan Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention generally relates to a container with functions of temperature indication and thermal storage, in particular to a container which is able to utilize a Greenhouse-like effect to extend heat preservation time, while indicating the current temperature by the color changes of a thermochromic material and adjusting the temperature of drinks to an optimum drinking temperature zone using a thermal storage material.

2. Description of the Related Art

With the improvement of living standards, people have begun to focus more on the details of life, and numerous products for improving those details have also started to emerge. For instance, during cold weather or attending outdoor activities like hiking, camping or picnicking, if drinks are carried in normal containers, a user may only have cold drinks instead of hot drinks when going outdoors. Therefore, bottles having heat preservation features have been developed. According to the research report of “Global Stainless Steel Insulation Cup Industry 2017 Market Developments and Future Trends”, the global stainless steel insulation cup market of 2016 had approached $3.6 billion, indicating a great market potential for insulated cups and related products.

Conventional insulated bottles often achieve heat preservation and extend the holding time by lowering the three heat transfer mechanisms such as thermal conduction, thermal convection, and thermal radiation. However, since heat slowly dissipates in a single direction heading out of the bottle, it is nearly impossible to actually reach a long holding time of heat according to the laws of physics. Conventional solutions to the aforementioned thermal energy loss were usually done by combining the container with an additional heating device. However, adding a heating device will result in a more complicated manufacturing process and increase the processing cost of the insulated container.

In addition, most insulated bottles do not include a temperature indication function, so the user may not know the current temperature of the drink inside. If the insulated bottle cannot display the temperature, there will be risks of burning the oral cavity and esophagus, and also potentially damaging ones health from frequently taking drinks that are too hot. On the other hand, one may also miss the best drinking time of certain drinks and the drinking experience may be negatively affected.

Therefore, it is necessary to develop a container with functions of temperature indication and thermal storage which is able to extend heat preservation time, display the temperature, and adjust the temperature of drinks to an optimum drinking temperature zone.

SUMMARY OF THE INVENTION

Therefore, it is a primary objective of the present invention to provide a container with functions of temperature indication and thermal storage, which is able to utilize a Greenhouse-like effect to extend heat preservation time, while indicating the current temperature by the color changes of a thermochromic material and adjust the temperature of drinks to an optimum drinking temperature zone using a thermal storage material, in order to solve the problems of the above mentioned conventional art.

To achieve the foregoing objective, the present invention provides a container with functions of temperature indication and thermal storage, comprising: an inner bottle containing a liquid; a thermochromic and thermal storage material layer disposed on an outer side of the inner bottle; and a first polymer layer disposed on an outer side of the thermochromic and thermal storage material layer, wherein the thermochromic and theimal storage material layer comprises: a thermal storage material adapted to undergo a phase change for absorbing or releasing thermal energy; and a thermochromic material mixed in the thermal storage material, and having at least two color changes depending on a temperature change, and wherein the first polymer layer comprises a wavelength-selective polymer, and the thermochromic and thermal storage material layer absorbs light passing through the first polymer layer.

In a preferred embodiment of the present invention, the foregoing container further comprises: a second polymer layer disposed on an outer side of the first polymer layer, and including the wavelength-selective polymer; and a medium layer disposed between the first polymer layer and the second polymer layer, wherein the thermochromic and thermal storage material layer absorbs light passing through the first polymer layer, the second polymer layer, and the medium layer.

In a preferred embodiment of the present invention, the medium layer is a vacuum layer.

In a preferred embodiment of the present invention, the endothermic peak and the exothermic peak of the thermochromic and thermal storage material layer lies in a range of a drinkable temperature.

In a preferred embodiment of the present invention, the optimum drinking temperature is in a range of 55° C. to 65° C.

In a preferred embodiment of the present invention, the wavelength-selective polymer is a polymer having a visible light transmittance and a near-infrared light transmittance of above 70%, and a mid-infrared light transmittance of below 10%.

In a preferred embodiment of the present invention, the thermochromic and thermal storage material includes saturated higher fatty acids.

The container with functions of temperature indication and thermal storage of the present invention has the following advantages:

(1) The container is able to effectively absorb the radiant heat of visible and near-infrared light by the polymer layer and the thermochromic and thermal storage material, and keep the radiant heat of mid-infrared light inside the container to create a Greenhouse-like effect and extend the heat preservation time of the drinks inside the container with functions of temperature indication and thermal storage.

(2) The container can achieve temperature indication functions by the phase change of the thermochromic and thermal storage material. Therefore preventing users from being injured by hot drinks while allowing users to control the best drinking time and reduce the need for secondary heating to save energy.

(3) The container with functions of temperature indication and thermal storage is able to hold the drinks in an optimum drinking temperature zone for a long time by the latent heat of solidification of the thermochromic and thermal storage material layer. The container with functions of temperature indication and thermal storage also possesses thermal insulation properties and the advantages of light weight.

(4) Compared with the material used in commercial insulated bottles, the polymer layer of the present invention has the advantages of low cost, robustness, and good processability.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a container with functions of temperature indication and thermal storage in accordance with an embodiment of the present invention.

FIG. 2 is a schematic view of a container with functions of temperature indication and thermal storage in accordance with another embodiment of the present invention.

FIG. 3 is a schematic view of a container with functions of temperature indication and thermal storage in accordance with another embodiment of the present invention.

FIG. 4 to FIG. 6 respectively show schematic views of the Greenhouse-like effect of a container with functions of temperature indication and thermal storage in accordance with an embodiment of the present invention.

FIG. 7 and FIG. 8 respectively show a container with functions of temperature indication and thermal storage in accordance with an example of the present invention.

FIG. 9 is a radiation property analysis chart of the polymer layer of a container with functions of temperature indication and theimal storage in accordance with an example of the present invention.

FIG. 10 is an FTIR and VMS analysis chart of the polymer layer of a container with functions of temperature indication and thermal storage in accordance with an example of the present invention.

FIG. 11 is a hemispherical radiation analysis chart of the thermochromic and thermal storage material layer of a container with functions of temperature indication and thermal storage in accordance with an example of the present invention.

FIG. 12 is a DSC analysis chart of the thermochromic and thermal storage material layer of a container with functions of temperature indication and thermal storage in accordance with an example of the present invention.

FIG. 13 is a schematic view of the temperature indication of the thermochromic and thermal storage material layer of a container with functions of temperature indication and thermal storage in accordance with an example of the present invention.

FIG. 14 is a schematic view of the temperature indication of a container with functions of temperature indication and thermal storage in accordance with an example of the present invention.

FIG. 15 is a schematic graph of the heat preservation function of a container with functions of temperature indication and thermal storage in accordance with an example of the present invention.

FIG. 16 is a line graph of the heat preservation curve of a container with functions of temperature indication and thermal storage in accordance with an example of the present invention.

FIG. 17 is a comparison between thermal simulations and experimental measurements of a container with functions of temperature indication and thermal storage in accordance with an example of the present invention.

FIG. 18 is a schematic view of the optimized design of a container with functions of temperature indication and thermal storage in accordance with an example of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The technical content of the present invention will become apparent by the detailed description of the following embodiments and the illustration of related drawings as follows. Further, the size and thickness of the components in the drawings are drawn for the ease of description and for better understanding of the invention; hence the present invention should not be limited thereto.

FIG. 1 is a schematic view of a container with functions of temperature indication and thermal storage in accordance with an embodiment of the present invention. As shown in FIG. 1, in an embodiment of the present invention, the container with functions of temperature indication and thermal storage 1 of the present invention may include an inner bottle 10, a thermochromic and thermal storage material layer 20, and a first polymer layer 30.

The inner bottle 10 is used to contain liquid, and may be formed of stainless steel, glass, ceramics or any material known in the art.

The thermochromic and thermal storage material layer 20 may be disposed on an outer side of the inner bottle 10, and may include a thermal storage material and a thermochromic material. The thermal storage material may be adapted to undergo a phase change for absorbing or releasing thermal energy. The heat source may be an internal or external source. The thermochromic material may be mixed or doped in the thermal storage material, and may have at least two color changes depending on temperature change. Therefore, the thermochromic and thermal storage material layer may possess temperature regulation functions by phase change as well as temperature indication functions to show the temperature range by displaying color changes. The thermochromic and thermal storage material layer 20 may include saturated higher fatty acids to achieve thermal storage functions. The endothermic peak and exothermic peak of the thermochromic and thermal storage material layer 20 may be in a range of an optimum drinking temperature, preferably 55° C.-65° C. That is, the endothermic peak of the thermochromic and thermal storage material layer 20 may be about 60-65° C. and the exothermic peak of the thermochromic and thermal storage material layer 20 may be about 55-60° C. Through different color combinations, the thermochromic and thermal storage material layer 20 can quickly inform the user of the current temperature of the liquid inside the container with functions of temperature indication and thermal storage. The thermochromic and thermal storage material layer 20 may further include thermosensitive capsules which display different colors to show various color combinations under different temperatures. The thermochromic and thermal storage material layer 20 may be disposed on an outer side of the inner bottle 10 in various shapes and designs to improve the visuals of the container with functions of temperature indication and thermal storage.

The first polymer layer 30 may be disposed on an outer side of the thermochromic and thermal storage material layer 20. The first polymer layer 30 may include a wavelength-selective polymer, and the thermochromic and thermal storage material layer 20 may absorb the light passing through the first polymer layer 30 having the wavelength-selective polymer. The light may include sunlight and/or other external light. Preferably, the wavelength-selective polymer may be a polymer having a visible light (having wavelength of about 0.4-0.75 μm) transmittance of above 70%, and a near-infrared light (having wavelength of about 0.75-1.4 μm) transmittance of above 70%, and a mid-infrared light (having wavelength of about 1.4-3 μm) transmittance of below 10%. Preferably, the thickness of the first polymer layer 30 may be below 5 mm, and more preferably below 3 mm, so as to achieve the goal of only using the wavelength-selective polymer to perform the light filtering effect without absorbing heat from the light.

FIG. 2 is a schematic view of a container with functions of temperature indication and thermal storage in accordance with another embodiment of the present invention. As shown in FIG. 2, in another embodiment of the present invention, the container with functions of temperature indication and thermal storage 2 of the present invention may further include a medium layer 40 and a second polymer layer 50. The second polymer layer 50 may be disposed on an outer side of the first polymer layer 30, and may including a wavelength-selective polymer. Preferably, the thickness of the second polymer layer 50 may be below 5 mm, and more preferably below 3 min, so as to achieve the goal of only using the wavelength-selective polymer to perform the light filtering effect without absorbing heat from the light. The medium layer 40 may be disposed between the first polymer layer 30 and the second polymer layer 50. The thermochromic and thermal storage material layer 20 may absorb the light passing through the first polymer layer 30 having the wavelength-selective polymer, the medium layer 40, and the second polymer layer 50 having the wavelength-selective polymer. The medium layer may be an air layer or a vacuum layer. The wavelength-selective polymer included in the first polymer layer 30 and the second polymer layer 50 may be the same or different.

FIG. 3 is a schematic view of a container with functions of temperature indication and thermal storage in accordance with another embodiment of the present invention. Wherein, part (a) of FIG. 3 is a schematic view of the whole structure of a container with functions of temperature indication and thermal storage in accordance with another embodiment of the present invention, and part (b) of FIG. 3 is a sectional view of the whole structure of a container with functions of temperature indication and thermal storage in accordance with another embodiment of the present invention. As shown in part (a) and (b) of FIG. 3, in another embodiment of the present invention, the container with functions of temperature indication and thermal storage 3 of the present invention may further include an anti-collision layer 60 to prevent the container with functions of temperature indication and thermal storage 3 from crashing and breaking. The container with functions of temperature indication and thermal storage 3 of the present invention may further include a stopper. The stopper may be formed of stainless steel, plastic, rubber, or any material known in the art.

The container with functions of temperature indication and thermal storage of the present invention utilizes the phase change of the thermal storage material, and the Greenhouse-like effect generated by the interaction of the thermal storage material and the polymer material to achieve great thermal storage effect, while utilizing the thermochromic material to show the temperature range.

With reference to FIG. 4 to FIG. 6, they are schematic views of the Greenhouse-like effect of a container with functions of temperature indication and thermal storage in accordance with an embodiment of the present invention.

As shown in FIG. 4, the term “Greenhouse effect” generally refers to the effect when short wavelength sunlight penetrates the glass and absorbed by the greenhouse, and then emits long wavelength infrared light. However, most part of the long wavelength infrared light cannot penetrate the glass and would be kept inside the greenhouse and raises the temperature of inside the greenhouse. The container with functions of temperature indication and thermal storage of the present invention also has a Greenhouse-like effect which is similar to the Greenhouse effect and improves thermal storage properties of the present invention.

More specifically, as shown in FIG. 5, applying Planck's law shown in Formula (1) and compare the average solar radiation flux spectrum and blackbody of AM1.5G. The blackbody is the thermochromic and thermal storage material layer of the present invention, with a freezing point of about 330K.

$\begin{matrix} {{E_{b\; \lambda}\left( {\lambda,T} \right)} = \frac{C_{1}}{\lambda^{5}\left\lbrack {{\exp \left( \frac{C_{2}}{\lambda \; T_{s}} \right)} - 1} \right\rbrack}} & {{Formula}\mspace{14mu} (1)} \end{matrix}$

In Formula (1), the unit being W/m² μm, E_(bλ) represents spectral blackbody emissive power, λ represents wavelength of the radiation emitted, C₁ being 3.74177×10⁸ Wμm⁴/m², C₂ being 1.43878×10⁴ μmK, and T_(s) represents absolute temperature of the surface. The vertical axis is the radiation flux, the horizontal axis is the wavelength, and the solid line represents AM1.5G, the dashed line represents 330K blackbody. The AM1.5G curve represents Surface solar radiation flux, and the optimum drinking temperature of the container with functions of temperature indication and thermal storage is between the ranges of about 328K-338K, thus represented as 330K. Therefore, the ideal properties of the thermochromic and thermal storage material layer will be the ability to absorb solar radiant heat of wavelength below 2.5 μm, and keep the solar radiant heat of wavelength above 2.5 μm inside the container with functions of temperature indication and thermal storage to create the Greenhouse-like effect.

Furthermore, as shown in FIG. 6, the ideal absorptance of radiation spectrum is illustrated. When the wavelength is between 0-2.5 μm, the ideal absorptance of the thermochromic and thermal storage material layer is 1, the ideal transmittance of the first polymer layer and the second polymer layer are also 1, and the ideal absorptance of the integrated region of the two is 1; when the wavelength is above 2.5 μm, the ideal absorptance of the thermochromic and thermal storage material layer can be any value, the ideal transmittance of the first polymer layer and the second polymer layer are 0, and the ideal absorptance of the integrated region of the two is 0.

With reference to FIG. 7 to FIG. 8, a container with functions of temperature indication and thermal storage are shown respectively in accordance with a preferred embodiment of the present invention.

FIG. 7 illustrates the multi-layer structure of the container with functions of temperature indication and thermal storage of the present invention. The container with functions of temperature indication and thermal storage of the present invention may further include a plurality of contact points. The plurality of contact points may be arranged between the inner bottle and the first polymer layer, so as to evenly distribute the thermochromic and thermal storage material layer.

Part (a) of FIG. 8 illustrates a side view of the container with functions of temperature indication and thermal storage of the present invention, and part (b) of FIG. 8 illustrates an upper view of the container with functions of temperature indication and thermal storage of the present invention, showing that the container with functions of temperature indication and thermal storage of the present invention does include the multi-layer structure illustrated in FIG. 7.

In addition, in a preferred embodiment of the present invention, the inner bottle is made of stainless steel, the first polymer layer and the second polymer layer are both made of polymers with a chemical formula of (C₅O₂H₈)_(n). Preferably, n should be between 10000-20000, when n is more than 20000, the structure will be brittle and crack easily; when n is less than 10000, the mechanical strength of the structure will decrease.

Preferably, the thermochromic and thermal storage material may include saturated higher fatty acids of 85% to 95% by weight of the thermochromic and thermal storage material layer. When the weight percentage is more than 95%, the content of saturated higher fatty acids is too high, and will have negative effects of causing the color display and changes being less obvious; when the weight percentage is less than 85%, the content of saturated higher fatty acids is too low, and will have negative effects of lowering the total phase change enthalpy. Preferably, the saturated higher fatty acid may be palmitic acid (C₁₆H₃₂O₂).

Preferably, the thermochromic and thermal storage material layer may further include a compound selected from the group consisting of Melamine Formaldehyde Resin, 3-N-p-tolyl-N-ethylamino-7-methyl-fluoran, 4,4-Isopropylidenediphenol (Bisphenol A), 1-Hexadecanol, 1-Octadecanol, 1-Docosanol and combinations thereof.

In an example of the present invention, the inner bottle is made of 304 stainless steel, the first polymer layer and the second polymer layer are both made of polymers with chemical formula of (C₅O₂H₈)_(n), and n being 10000-20000. The thermochromic and thermal storage material layer includes red temperature indication material and blue temperature indication material. The red temperature indication material includes 90 wt % of palmitic acid and 10 wt % of red temperature sensitive material. The red temperature sensitive material includes 1-5% Melamine Formaldehyde Resin, 2-10% 3-N-p-tolyl-N-ethylamino-7-methyl-fluoran, 5-15% Bisphenol A, 10-15% 1-Hexadecanol, 15-25% 1-Octadecanol, and 25-40% 1-Docosanol. Wherein the red temperature indication material displays bright red when below 55° C., and displays light pink when above 55° C. The blue temperature indication material includes 90 wt % of palmitic acid and 10 wt % of blue temperature sensitive material. The blue temperature sensitive material includes 1-5% Melamine Formaldehyde Resin, 2-10% 3-(4-Dimethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azaphthalide, 5-15% Bisphenol A, 25-40% 1-Octadecanol, and 25-40% 1-Docosanol. Wherein the blue temperature indication material displays dark blue when below 65° C., and displays light blue when above 65° C.

In addition, an analysis of the first polymer layer, the second polymer layer, and the thermochromic and thermal storage material layer according to an example of the present invention have been conducted. Since the first polymer layer and the second polymer layer are the same in this example, they will be referred as the polymer layer hereinafter.

Analysis of the Polymer Layer

With reference to FIG. 9, a radiation property analysis chart of the polymer layer of a container with functions of temperature indication and thermal storage is shown in accordance with an example of the present invention. As shown in the chart, a polymer having thickness of 1.6 mm is used as the polymer layer for analysis. The result shows a high transmittance when the wavelength is below 2.2 μm, and when the wavelength is above 2.2 μm, the transmittance is below 0.1, meaning that the polymer layer can effectively absorb the radiant heat of visible light and near-infrared light, and keep the radiant heat of mid-infrared light to create a Greenhouse-like effect inside the container with functions of temperature indication and thermal storage which extends heat preservation time.

With reference to FIG. 10, an FTIR and VMS analysis chart of the polymer layer of a container with functions of temperature indication and thermal storage is shown in accordance with an example of the present invention. As shown in the chart, a polymer having thickness of 3 mm is used as the polymer layer for analysis under an incident angle of 0 degrees. The result shows that regardless of using FTIR or VMS, the transmittance is almost 0 when the wavelength is above 2.2 μm; and when the wavelength is between 0.4 μm-1.5 μm, the transmittance reaches above 0.85, meaning that the Greenhouse-like effect can be generated.

Analysis of the Thermochromic and Thermal Storage Material Layer

With reference to FIG. 11, a hemispherical radiation analysis chart of the thermochromic and thermal storage material layer of a container with functions of temperature indication and thermal storage is shown in accordance with an example of the present invention. A polymer having thickness of 3 mm is used as the polymer layer for analysis under an incident angle of 8 degrees. The result shows that a absorption peak occurred in the visible light zone having wavelength of 0.4 μm-0.7 μm, with an absorptance reaching 0.98, and a absorption peak also occurred in the near-infrared light zone having wavelength of 0.8 μm-1.4 μm, with an absorptance above 0.5, meaning that the thermochromic and thermal storage material layer is capable of absorbing sunlight radiation.

With reference to FIG. 12, a DSC analysis chart of the thermochromic and thermal storage material layer of a container with functions of temperature indication and thermal storage is shown in accordance with an example of the present invention. FIG. 12 illustrates the full cycle including the process of heating up and cooling down. The result shows that when the temperature rises to about 63° C., the thermochromic and thermal storage material layer starts to melt and generates an endothermic peak, the latent heat of melting (ΔH_(m)) is 183 J/g, hence the heat absorption effect of the phase change can be utilized to lower the temperature of the liquid inside the container with functions of temperature indication and thermal storage to about 63° C.; when the temperature is lowered to 60° C., the latent heat of fusion (ΔH_(f)) is −180 J/g, the thermochromic and thermal storage material layer starts to fuse and generates an exothermic peak, hence the heat release effect of the phase change can be utilized to keep the temperature of the liquid inside the container with functions of temperature indication and thermal storage at about 60° C. In addition, since the latent heat of fusion of the thermochromic and thermal storage material layer is quite large, a small amount of thermochromic and thermal storage material will be enough to hold the water temperature inside the container with functions of temperature indication and thermal storage.

With reference to FIG. 13, a schematic view of the temperature indication of the thermochromic and thermal storage material layer of a container with functions of temperature indication and thermal storage is shown in accordance with an example of the present invention. FIG. 13 respectively shows the temperature display of the red and blue temperature indication material under different temperature. As shown in the center region of part (a) and the center region of part (b) of FIG. 13, when at 70° C., the red and blue temperature indication material both display a lighter color, indicates that the temperature is too high considering the drinking experience and potential health risks. As shown in the center region of part (c) of FIG. 13, when at 60° C. the blue temperature indication material displays dark blue, and the red temperature indication material displays light pink as shown in the center region of part (d) of FIG. 13, indicates that the temperature is moderate which provides the best drinking experience without potential health risks for being too hot. As shown in the center region of part (e) of FIG. 13, when at 50° C., the blue temperature indication material displays dark blue, and the red temperature indication material displays bright red as shown in the center region of part (f) of FIG. 13, indicates that the temperature is relatively low which may negatively affect the drinking experience.

With reference to FIG. 14, a schematic view of the temperature indication of a container with functions of temperature indication and thermal storage is shown in accordance with an example of the present invention. As shown in part (a) of FIG. 14, when the temperature of the liquid inside the container with functions of temperature indication and thermal storage is below 55° C., bright red is displayed; as shown in part (b) of FIG. 14, when the temperature of the liquid inside the container with functions of temperature indication and thermal storage is between 55° C.-65° C., light pink is displayed.

With reference to FIG. 15, a schematic graph of the heat preservation function of a container with functions of temperature indication and thermal storage is shown in accordance with an example of the present invention. The experiment took place at AM10:00-PM5:00, 2018/01/15, in Hsinchu, Taiwan. A hot liquid of 85° C. was poured into both the container with functions of temperature indication and thermal storage of the present invention and a conventional (or, commercially available) insulated bottle, and the containers were placed under the sun to observe and compare the temperature change through time. As shown in FIG. 15, the water temperature inside the conventional insulated bottle decreased almost linearly, dropping to the optimum drinking temperature zone in about 4 hours, and maintained this temperature for 3 hours. On the other hand, the water temperature inside the container with functions of temperature indication and thermal storage of the present invention dropped to 67° C. in about 5 minutes, and maintained this temperature for nearly 6 hours. That is, the preservation time within the optimum drinking temperature zone of the container with functions of temperature indication and thermal storage of the present invention is two times longer than that of the conventional insulated bottle.

With reference to FIG. 16, a line graph of the heat preservation curve of a container with functions of temperature indication and thermal storage is shown in accordance with an example of the present invention. Under a condition without sunlight radiation, the vertical axis represents the temperature and the horizontal axis represents time, the optimum drinking temperature zone is set between 55° C.-65° C., part (a) represents the conventional insulated bottle, and part (b) represents the container with functions of temperature indication and thermal storage of the present invention. As shown in part (a) of FIG. 16, the water temperature inside the conventional insulated bottle decreased linearly, required 40 minutes to reach the optimum drinking temperature, and maintained in the optimum drinking temperature zone (II) for only 36 minutes. On the other hand, as shown in part (b) of FIG. 16, in the temperature adjustment zone (I) resulted by the effects of the thermal storage material layer, the water temperature inside the container with functions of temperature indication and thermal storage of the present invention required only 7 minutes to reach the optimum drinking temperature, and maintained in the optimum drinking temperature zone (II) for as long as 63 minutes.

With reference to FIG. 17, showing a comparison between thermal simulations and experimental measurements of a container with functions of temperature indication and thermal storage in accordance with an example of the present invention. The software used is COMSOL Multiphysics®, the fin heat transfer module supports the simulation of multiple radiation phenomena, and includes dedicated solver to simulate thermal radiation coupled convection and conduction. The geometric parameters, material parameters and boundary conditions of the container with functions of temperature indication and thermal storage were input and being simplified under limited computing resources. The material parameters include the thermal conductivity of the stainless steel inner bottle, the transmittance of the polymer layer, the thermal conductivity of the polymer layer, the absorptance of the thermochromic and thermal storage material layer and the thermal conductivity of the thermochromic and thermal storage material layer. The boundary conditions include solar irradiance, ambient temperature, and environmental heat convection coefficient. The simulated temperature at each time period of the container with functions of temperature indication and thermal storage were compared with the experimental results of FIG. 15 to verify the accuracy of the simulation and used to optimize the design of the container with functions of temperature indication and thermal storage of the present invention.

As shown in FIG. 17, the temperature change over time results of the actual value and the simulated value being close to each other having an average temperature error within 2° C., represents that the simulation system can accurately simulate the actual status of the container with functions of temperature indication and thermal storage of the present invention.

With reference to FIG. 18, a schematic view of the optimized design of a container with functions of temperature indication and thermal storage is shown in accordance with an example of the present invention. A table of levels was specifically designed for the container with functions of temperature indication and thermal storage of the present invention. A container with functions of temperature indication and thermal storage having a content volume of 500 mL was used as the standard, and three factors being the shape, quantity of fins and fin shape were selected respectively and set three levels respectively for each factor. Next, an orthogonal table was designed for the optimization using the Taguchi method. Since there are three factors having three levels, L₉(3⁴) orthogonal table was selected and perform 9 experiments in total. An adaptive function was then designed to obtain the optimization parameter. In this example, besides considering temperature adjustment and heat preservation time, the container was also designed to be an outdoor portable container, so the weight of the container with functions of temperature indication and thermal storage was also considered. Finally, a factor response table is obtained by calculating the result of the adaptive function, and the factor response table is used to frond the sensitive factor and the optimization parameter.

As shown in part (a) and part (b) of FIG. 18, the optimization parameter was: the stainless steel inner bottle having diameter D/height H of 60 mm/180 mm, and the thermochromic and thermal storage material layer having thickness T of 6.5 mm. As shown in part (c) of FIG. 18, the number of fin 18 is 5, the fin having length/thickness of 5.5 mm/5.5 mm, the section of ring fin is rectangular. After the optimization, the container with functions of temperature indication and thermal storage can cool 85° C. liquid to 65° C. in 5 minutes, maintain in the optimum drinking temperature zone for over 300 minutes, and weight only 800 g.

As described above, the container with functions of temperature indication and thermal storage of the present invention is able to utilize a Greenhouse-like effect to extend heat preservation time, while indicating the current temperature by color changes and adjust the temperature of drinks to an optimum drinking temperature zone, and may also meet the needs of various users by adjusting the ratio of the first polymer layer, second polymer layer, and the thermochromic and thermal storage material.

While the means of specific embodiments in present invention has been described by reference drawings, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of the invention set forth in the claims. 

What is claimed is:
 1. A container with functions of temperature indication and thermal storage, comprising: an inner bottle containing a liquid; a thermochromic and thermal storage material layer disposed on an outer side of the inner bottle; and a first polymer layer disposed on an outer side of the thermochromic and thermal storage material layer, wherein the thermochromic and thermal storage material layer comprises: a thermal storage material adapted to undergo a phase change for absorbing or releasing thermal energy; and a thermochromic material mixed in the thermal storage material, and having at least two color changes depending on a temperature change, wherein the first polymer layer comprises a wavelength-selective polymer, and the thermochromic and thermal storage material layer absorbs light passing through the first polymer layer.
 2. The container with functions of temperature indication and thermal storage of claim 1, wherein an endothermic peak and an exothermic peak of the thermochromic and thermal storage material layer lies in a range of an optimum drinking temperature.
 3. The container with functions of temperature indication and thermal storage of claim 2, wherein the optimum drinking temperature is in a range of 55° C. to 65° C.
 4. The container with functions of temperature indication and thermal storage of claim 1, wherein the wavelength-selective polymer is a polymer having a visible light transmittance and a near-infrared light transmittance of above 70%, and a mid-infrared light transmittance of below 10%.
 5. The container with functions of temperature indication and thermal storage of claim 1, wherein the thermochromic and thermal storage material includes saturated higher fatty acids.
 6. The container with functions of temperature indication and thermal storage of claim 1, wherein the container further comprises: a second polymer layer disposed on an outer side of the first polymer layer, and including the wavelength-selective polymer; and a medium layer disposed between the first polymer layer and the second polymer layer, wherein the thermochromic and thermal storage material layer absorbs light passing through the first polymer layer, the second polymer layer, and the medium layer.
 7. The container with functions of temperature indication and thermal storage of claim 6, wherein an endothermic peak and an exothermic peak of the thermochromic and thermal storage material layer lies in a range of an optimum drinking temperature.
 8. The container with functions of temperature indication and thermal storage of claim 7, wherein the optimum drinking temperature is in a range of 55° C. to 65° C.
 9. The container with functions of temperature indication and thermal storage of claim 6, wherein the wavelength-selective polymer is a polymer having a visible light transmittance and a near-infrared light transmittance of above 70%, and a mid-infrared light transmittance of below 10%.
 10. The container with functions of temperature indication and thermal storage of claim 6, wherein the thermochromic and thermal storage material includes saturated higher fatty acids.
 11. The container with functions of temperature indication and thermal storage of claim 6, wherein the medium layer is a vacuum layer.
 12. The container with functions of temperature indication and thermal storage of claim 11, wherein an endothermic peak and an exothermic peak of the thermochromic and thermal storage material layer lies in a range of an optimum drinking temperature.
 13. The container with functions of temperature indication and thermal storage of claim 12, wherein the optimum drinking temperature is in a range of 55° C. to 65° C.
 14. The container with functions of temperature indication and thermal storage of claim 11, wherein the wavelength-selective polymer is a polymer having a visible light transmittance and a near-infrared light transmittance of above 70%, and a mid-infrared light transmittance of below 10%.
 15. The container with functions of temperature indication and thermal storage of claim 11, wherein the thermochromic and thermal storage material includes saturated higher fatty acids. 